For many infrared imaging devices, various calibration procedures may be performed during manufacturing, testing, and/or operation to correct non-uniformities or otherwise reduce noise associated with the infrared imaging devices. Calibration data (also referred to as calibration terms) produced during such calibration procedures are typically stored in a non-volatile memory and applied to the infrared imaging devices and/or captured images to correct non-uniformities or otherwise reduce noise that may appear in the captured images. However, as various characteristics of various components of the infrared imaging devices change with passage of time and/or with use, the calibration terms gradually become stale (e.g., less effective), resulting in a calibration drift.
To correct calibration drifts, infrared imaging devices typically need to be recalibrated at a calibration station and/or using an internal calibration shutter mechanism embedded into the infrared imaging devices. However, a calibration station may be unavailable, or using one may be cumbersome. Internal calibration shutter mechanisms may also be unavailable for many infrared imaging devices, especially for small form factor and/or low cost devices.
Some infrared imaging devices may be capable of performing shutterless non-uniformity correction (NUC) methods using images captured during operation of the device, so as to further correct non-uniformities or otherwise reduce noise in addition to applying the calibration terms. However, such methods may not be sufficient to quickly compensate for calibration drifts, because as the calibration drifts worsen it may take an unacceptably long time for the shutterless NUC methods to produce reasonable results after the infrared imaging devices start capturing images.